fix(downloads): harden queue reordering and summary stats

src/utils/downloadSummary.test.ts

@@ -37,6 +37,27 @@ describe('download summaries', () => {
     });
   });
 
+  it('treats completed downloads as having no remaining bytes despite stale progress', () => {
+    expect(summarizeDownloads([
+      item('done', {
+        status: 'completed',
+        totalBytes: 40 * 1024 ** 2,
+        downloadedBytes: 40 * 1024 ** 2,
+      }),
+    ], {
+      done: progress('done', {
+        downloaded_bytes: 40 * 1024 ** 2 - 555 * 1024,
+        total_bytes: 555 * 1024,
+      }),
+    })).toEqual({
+      itemCount: 1,
+      activeCount: 0,
+      downloadedBytes: 40 * 1024 ** 2,
+      remainingBytes: 0,
+      remainingIsEstimated: false,
+    });
+  });
+
   it('does not present partial byte totals as complete aggregates', () => {
     expect(summarizeDownloads([
       item('known', { totalBytes: 100, downloadedBytes: 20 }),

src/utils/downloadSummary.ts

@@ -42,11 +42,13 @@ const effectiveByteState = (
   const totalBytes = usesStoredMediaTotal
     ? usableBytes(download.totalBytes)
     : usableBytes(progress?.total_bytes) ?? usableBytes(download.totalBytes);
-  const downloadedBytes =
-    usableBytes(progress?.downloaded_bytes) ??
-    usableBytes(download.downloadedBytes) ??
-    (download.status === 'completed' ? totalBytes : undefined) ??
-    (canInferNoDownloadedBytes(download) ? 0 : undefined);
+  const downloadedBytes = download.status === 'completed'
+    ? usableBytes(download.downloadedBytes) ??
+      usableBytes(progress?.downloaded_bytes) ??
+      totalBytes
+    : usableBytes(progress?.downloaded_bytes) ??
+      usableBytes(download.downloadedBytes) ??
+      (canInferNoDownloadedBytes(download) ? 0 : undefined);
   const totalIsEstimate = usesStoredMediaTotal
     ? storedTotalIsEstimate
     : (progress?.total_is_estimate ?? storedTotalIsEstimate) === true;
@@ -89,6 +91,13 @@ export const summarizeDownloads = (
       }
     }
 
+    if (download.status === 'completed') {
+      // A completed row is terminal even when a delayed progress event still
+      // carries an old partial denominator. Never expose that stale value as
+      // remaining work in the aggregate status bar.
+      continue;
+    }
+
     if (
       state.totalBytes === undefined ||
       state.downloadedBytes === undefined ||

src/utils/downloadTableColumns.ts

@@ -15,7 +15,7 @@ export const DEFAULT_COLUMN_ORDER = [
 export const DEFAULT_COLUMN_WIDTHS = [340, 100, 220, 100, 80, 170] as const;
 export const COLUMN_MINIMUMS = [160, 58, 92, 58, 48, 144] as const;
 // Width of the fixed action rail shown while hovering a row.
-export const DOWNLOAD_ACTIONS_COLUMN_WIDTH = 120;
+export const DOWNLOAD_ACTIONS_COLUMN_WIDTH = 84;
 // Keep the fixed rail clear of the viewport edge and horizontal scrollbar.
 export const DOWNLOAD_ACTIONS_VIEWPORT_INSET = 8;